Peter,

Thank you for reaching out to us with your inquiry.

Kindly note, you would not need to have an HVAC guy install this unit at all. A general contractor or handy man may complete this job at a lower cost. The unit has a chimney with venting openings at the top, these openings will be used to allow the air being pulled up to exit back into the room. There is really no disavantages or advantages with either installation, you are simply installing it to your needs.

Feel free to contact us with any and all questions.

Regards, Customer support